Lubricant



Patented Apr. 26, 1949 UNITED STATES PATENT OFFICE LUBRICANT Ohio NoDrawing. Original application December 24,

1941, Serial No. 424,362. Divided and this application November 23,1943, Serial No. 511,472

2 Claims. (01. 252-27) The present invention relates to lubricants, thisapplication being a division of our application Serial No. 424,362,filed December 24, 1941, now Patent No. 2,346,357, April 11, 1944, andit has among its objects the provision of improved lubrication in hightemperature, such as in internal combustion engines. Other objects andadvantages will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, the invention,then, comprises the features hereinafter fully described, andparticularly pointed out in the claims, the following descriptionsetting forth in detail certain illustrative embodiments of theinvention, these being indicative however, of but a few of the variousways in which the principle of the invention may be employed.

The lubricant base may be a usual lubricating oil of viscosity desiredin view of particular duty contemplated, or for instance 45 to 200 sec.S. U. at 210 F. We have found that salts of metals having oxidationactivity or which are oxidation catalysts not particularly at crankcasetemperature but at higher temperature promote diminution of carbonaceousdeposits outstandingly, and in combination with what we term an antioxidant give results much better than the total of the respective agentsalone, anti-oxidant here having a meaning not as with gasoline but as aninhibitor for metal catalysts such as iron, copper, or lead. It isparticularly remarkable that an agent of oxidizing character and whoseactivity tends primarily to be antagonistic to antioxidant action shouldwork to these ends. The salts of metals constituting the oxidationcatalysts comprise: naphthenates; salts of acid radicals such as of talloil or sulphurized tall oil; acids derived from the oxidation ofpetroleum fractions or polymers; xanthic, i. e. acids of the type Roe-g3in which R is alkyl, aryl, alkaryl and suificient to solubilize themetal compound; medium molecular weight fatty acids chosen so that theresulting salt will have -30 carbon atoms; acids derived from saponifiedwool fat (degras) with or without the alcohol, and the Wool fat may besulphurized e. g. with P2S5, before or after hydrolysis; and forconciseness such acids are hereinafter designated organic acids of lowvolatility the stated salts of which promote diminution of carbonaceousdeposits. The naphthenates may also be chlorinated or halogenated, andin some cases sulphurized. The metals above referred to are chromium,also vanadium, manganese, cobalt and molybdenum. In general, /2 to 2 percent, or more, up to 3 per cent, of the metal compound may be used. Themetal salts are used with the said anti-oxidant agents. These agentscomprise sulphur-containing compounds such as P2S5 treated degras, P285treated poly olefins, P285 treated distilled cashew nut shell oil, etc.Up to 3 per cent, preferably 2 to 2 per cent of such agent additive tothe metal compounds may be employed.

As an example: A lubricant is made up of S. A. E. 20 lubricating oil and0.5 per cent of chromium naphthenate and 1.5 per cent of the reactionproduct of P285 on degras.

As another example: A lubricant is made up with a similar oil and 0.5per cent of chromium naphthenate and 2 per cent of the reaction productof P285 on polyolefin.

As illustrating the properties of such lubricants, the followingtest-results are noted in summary, in which F is bad or worse than theoil alone, i. e. over 30 mg. of lacquer and over 7 per cent of carbonresidue, C is mediocre, i. e. 10-30 mg. of lacquer, and 3.0-7.0 per centcarbon residue, and A is excellent, i. e. less than 10 mg. of lacquerand 'less than 3.0 per cent of carbon residue.

The carbon residue is determined by exposing a 2.5 g. sample of thelubricant in a mm. diameter Petri glass dish in an electric furnace for16 hours at 525 F., followed by 6 hours at 750 F. The carbon suspensionis determined by suspending 5 per cent by volume of carbon in thelubricant, and a cc. sample of the suspension in a 100 cc. graduate isset in an oven at 200 F., and the number of cc. of clear oil is measuredat intervals. The oxidation and lacquer is determined by exposing thelubricant in the presence of metals, iron and copper, at a temperatureof 310 F. for 65 hours by blowing air through at the rate of 30 litersper hour.

Other modes of applying the principle of the posits in the combustionzone of internal combustion engines and producing high stability in theI crank-case, which comprises a lubricating oil and one-fourth to threeper cent of:r-the:'reaction product of phosphorus sulphide on deg raisand one-half to three per cent of chromiurn naph' thenate.

2. A lubricant promoting -combustion= o1deposits in the combustion zoneof internalcombus tion engines and producing high'stability in the'crank-case, which comprises a lubricatingoil and one-fourth to three percent of the reaction prod uct of phosphorus sulphide on degras, andonehalf to three percent of a salt of a metal from periodic group VI andthose with atomic weight under 55 in the adjoining groups V and VII withan organic acid of low volatility the stated salts of which promotediminution of carbonaceous deposits.

ROBERT- E. BURK.

EVERETT C. HUGHES.

REFERENCES CITED The following references are of record in the file ofthispatentz" UNITED STATES PATENTS Number Name Date 2,151,285 ToussaintMar. 21, 1939 2,169,155 Lincoln et a1 Aug. 8, 1939 2,261,047 Asseff;Oct. 28, 1941 2,316,084 Loane et a1. Apr. 6, 1943 2,331,923 MusselmanOct. 19, 1943 2,346,357 Burk et a1. Apr. 11, 1944

